Testing PCIe on the Raspberry Pi 5

Testing PCIe on the Raspberry Pi 5(jeffgeerling.com)

86 points by cedel2k1 2 years ago | 8 comments

johnklos 2 years ago |

PCIe does fix the main complaint most people have with Raspberry Pis: the lack of reliable storage. While USB is perfectly fine for spinning rust, it's not quite ideal for SSDs, and we all have an SD card failure story or two.

It's interesting that the PCIe lane can be driven at PCIe 3.0 speeds. That goes a long way to helping to make up for the fact that it's just one lane. Having used various PCIe cards on a RockPro64, it's nice to see more options.

I'm a little surprised that UEFI isn't available at launch, but here's to hoping that won't take too long.

Good stuff, and I'm happy to see the progress. I just wish the company hadn't gone off the deep end.

naruhodo 2 years ago | |

I'm definitely learning some things today. Geerling's video[1] low-key sells the merits of the Rock 5B, which performs even better, though it's more expensive.

Geerling reviews that device here[2] and compares it to the RPi 4 back in February.

I was excited about the Pi 5 yesterday. And now more information has just left me uncertain. I think I need even more information.

Apparently there will be an M.2 NVMe hat in early 2024[3] so I guess that has to be factored into the price calculations for an RPi5.

[1] https://www.youtube.com/watch?v=nBtOEmUqASQ&t=566s

[2] https://www.jeffgeerling.com/blog/2023/rock-5-b-not-raspberr...

[3] https://www.jeffgeerling.com/blog/2023/answering-some-questi...

chris_j 2 years ago | |

What is it that makes USB perfectly fine for spinning rust but not quite ideal for SSDs?

I've been booting a couple of Pi 4s from USB SSDs for a while, in order to avoid relying on SD cards, but I'm not really familiar with what all of the implications of this are.

johnklos 2 years ago | | |

Oh - I'm just talking about speed. Of course there's no problem using SSDs aside from that. I'm running several older Pis off of SATA SSDs connected via USB 2, for better speed and reliability than SD cards.

For spinning rust, two fast (220 MB/sec) drives don't max out the single USB 3 channel on a Raspberry Pi 4. I have one colocated with two software mirrored 8 TB drives, with UASP, and I can get the full 220 MB/sec per drive at the same time with that setup.

extraduder_ire 2 years ago | |

Does the pi 4 even have official UEFI? I thought it was a third-party thing.

I think jeff did this testing on a pre-release firmware, so that and other features may be coming.

johnklos 2 years ago | | |

Not official as in it doesn't come from the Raspberry Pi people, but official as in it's what everyone who wants UEFI uses.

https://github.com/pftf/RPi4

Sending Pi 5s to people who're going to review them before the release makes sense, but of course it'd have been nice if they sent them to people who contribute important pieces of the ecosystem, too.

rnk 2 years ago |

If you have an interest in ras pi - especially for tech info interesting to a programmer - you'll probably enjoy the stuff that Jeff Geerling puts out. He has youtube videos and tries out things that software engineers are likely interested in. Love his stuff.